Digital system and power on reset circuit thereof

Abstract

The invention is applied to the technical field of power reset circuit design, and provides a digital system and a power on reset circuit thereof. The circuit thereof comprises a first register set, a first reset signal producing unit and a logic adding unit, wherein the first reset signal producing unit is used for logically comparing the value of the first register set with a preset random number after the digital system is powered on; if the comparison between the value of the first register set and the preset random number is different, a reset signal is sent for the digital circuit to bereset in the digital system, and the reset signal is simultaneously used as the enable signal of the first register set; when the comparison between the value of the first register set and the presetrandom number is the same, the reset signal is stopped sending for the digital circuit to be reset in the digital system; and the logic adding unit is used for adding a preset value to the value of the first register set after the digital system is powered on and the first register set receives the enable signal. The pulse width of the reset signal sent by the reset signal producing unit is at least more than one clock period, thereby having strong reliability and guaranteeing regular work of the digital system.

Description

technical field [0001] The invention belongs to the technical field of power-on reset circuit design, in particular to a digital system and a power-on reset circuit. Background technique [0002] The power-on reset circuit is used to realize the function of resetting the counters or register groups in the digital system when various complex digital systems (such as: CPU, etc.) are powered on once or powered on after a power failure, and its reliability Particularly important. [0003] The power-on reset circuit provided by the prior art is designed with an analog circuit. In some special power-on situations, such as: slow power-on or fast power-on, etc., the power-on reset circuit designed with an analog circuit is likely to provide a pulse width that is too narrow. The power-on reset signal causes the digital system to not work normally and has poor reliability. Contents of the invention [0004] The purpose of the embodiments of the present invention is to provide a po...

AI Technical Summary

Problems solved by technology

[0004] The purpose of the embodiments of the present invention is to provide a power-on reset circuit for a digital system, which aims to solve the problem that the power-on reset circuit designed with an analog circuit in the prior art has poor reliability and easily leads to the problem that the digital system cannot work normally.

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